/**
 * Xero Payroll Tools
 * Handles payroll operations: pay runs, pay slips, leave, timesheets
 * Note: This uses the Xero Payroll API which is separate from Accounting API
 */

import { XeroClient } from '../clients/xero.js';
import type { Tool } from '@modelcontextprotocol/sdk/types.js';

export function getTools(_client: XeroClient): Tool[] {
  return [
    // List pay runs
    {
      name: 'xero_list_pay_runs',
      description: 'List all pay runs. Pay runs are payroll processing batches.',
      inputSchema: {
        type: 'object',
        properties: {
          page: { type: 'number', description: 'Page number (default 1)' },
          where: { type: 'string', description: 'Filter expression (e.g., Status=="POSTED")' },
          order: { type: 'string', description: 'Order by field' }
        }
      }
    },

    // Get pay run
    {
      name: 'xero_get_pay_run',
      description: 'Get a specific pay run by ID. Returns pay run details including pay slips.',
      inputSchema: {
        type: 'object',
        properties: {
          payRunId: { type: 'string', description: 'Pay run ID (GUID)' }
        },
        required: ['payRunId']
      }
    },

    // List pay slips
    {
      name: 'xero_list_pay_slips',
      description: 'List all pay slips. Pay slips show individual employee payment details.',
      inputSchema: {
        type: 'object',
        properties: {
          page: { type: 'number', description: 'Page number (default 1)' },
          where: { type: 'string', description: 'Filter expression' },
          order: { type: 'string', description: 'Order by field' }
        }
      }
    },

    // Get pay slip
    {
      name: 'xero_get_pay_slip',
      description: 'Get a specific pay slip by ID. Returns detailed pay slip information.',
      inputSchema: {
        type: 'object',
        properties: {
          paySlipId: { type: 'string', description: 'Pay slip ID (GUID)' }
        },
        required: ['paySlipId']
      }
    },

    // List leave applications
    {
      name: 'xero_list_leave_applications',
      description: 'List all leave applications (vacation, sick leave, etc.).',
      inputSchema: {
        type: 'object',
        properties: {
          page: { type: 'number', description: 'Page number (default 1)' },
          where: { type: 'string', description: 'Filter expression (e.g., EmployeeID==Guid("...")' },
          order: { type: 'string', description: 'Order by field' }
        }
      }
    },

    // Create leave application
    {
      name: 'xero_create_leave_application',
      description: 'Create a leave application for an employee.',
      inputSchema: {
        type: 'object',
        properties: {
          employeeId: { type: 'string', description: 'Employee ID (GUID)' },
          leaveTypeId: { type: 'string', description: 'Leave type ID (GUID)' },
          title: { type: 'string', description: 'Leave title/description' },
          startDate: { type: 'string', description: 'Start date (YYYY-MM-DD)' },
          endDate: { type: 'string', description: 'End date (YYYY-MM-DD)' },
          description: { type: 'string', description: 'Leave description' }
        },
        required: ['employeeId', 'leaveTypeId', 'startDate', 'endDate']
      }
    },

    // List timesheets
    {
      name: 'xero_list_timesheets',
      description: 'List all timesheets. Timesheets track employee hours worked.',
      inputSchema: {
        type: 'object',
        properties: {
          page: { type: 'number', description: 'Page number (default 1)' },
          where: { type: 'string', description: 'Filter expression' },
          order: { type: 'string', description: 'Order by field' }
        }
      }
    },

    // Create timesheet
    {
      name: 'xero_create_timesheet',
      description: 'Create a timesheet for an employee.',
      inputSchema: {
        type: 'object',
        properties: {
          employeeId: { type: 'string', description: 'Employee ID (GUID)' },
          startDate: { type: 'string', description: 'Timesheet start date (YYYY-MM-DD)' },
          endDate: { type: 'string', description: 'Timesheet end date (YYYY-MM-DD)' },
          timesheetLines: {
            type: 'array',
            items: {
              type: 'object',
              properties: {
                earningsRateId: { type: 'string', description: 'Earnings rate ID (GUID)' },
                trackingItemId: { type: 'string', description: 'Tracking item ID (GUID)' },
                numberOfUnits: { type: 'array', items: { type: 'number' }, description: 'Hours per day (7 values)' }
              }
            },
            description: 'Timesheet lines with hours per day'
          }
        },
        required: ['employeeId', 'startDate', 'endDate']
      }
    }
  ];
}

export async function handlePayrollTool(
  toolName: string,
  args: Record<string, unknown>,
  _client: XeroClient
): Promise<unknown> {
  // Note: Payroll API is separate and requires different endpoint/authentication
  // This is a placeholder implementation showing the structure
  
  switch (toolName) {
    case 'xero_list_pay_runs':
    case 'xero_get_pay_run':
    case 'xero_list_pay_slips':
    case 'xero_get_pay_slip':
    case 'xero_list_leave_applications':
    case 'xero_create_leave_application':
    case 'xero_list_timesheets':
    case 'xero_create_timesheet':
      return {
        message: 'Payroll API integration pending',
        note: 'Xero Payroll API requires separate authentication and endpoints. This is a placeholder implementation.',
        tool: toolName,
        args
      };

    default:
      throw new Error(`Unknown payroll tool: ${toolName}`);
  }
}
